Air-conditioning apparatus



Jan. 7, 1958 G. BUNGAS 2,819,044

AIR-CONDITIONING APPARATUS Filed Aug. 30, 1955 so fr" IE" IN V EN TOR.GEORGE BUNGAS.

Madm/d fili W ATTORNEYS,

AlR-CONDITION ING APPARATUS George Bungas, Pittsburgh, Pa. ApplicationAugust 30, 1955, Serial No. 531,459

Claims. (Cl. 2579) My invention relates to air-conditioning apparatus,and consists in certain new and useful improvements in construction.

The apparatus of the invention embodies in a unitary structure meanslthat are operable in warm weather to cool the atmosphere of a home orother building, while in the cold season the apparatus operates to heatthe atmosphere.

Essentially the apparatus of the invention comprises a tank for a bodyof water, or other suitable liquid, and in such body a plenum chamberhaving heat-conducting walls is submerged. A blower is arranged topropel air through such chamber into the space or atmosphere to beconditioned. Heat-exchange means develop temperatures in the body ofwater at variance with the temperature of the air owing through theplenum chamber, whereby there is a transfer of heat between the owingair and the body of water, with the effect that the owing air isthermally conditioned for the purpose intended. As thus far describedthe apparatus lies in the domain of the prior art.

The object of my invention is to provide improvements in theconstruction and in the structural organization of apparatus of the sortmentioned, whereby thermal eliiciency in greater measure is obtained,and a more commercially practical apparatus realized.

In the accompanying drawings an apparatus embodying the invention isillustrated, in which:

Fig. l is a view of the apparatus in side elevation;

Fig. 2 is a view of the same vertical section; and

Fig. 3 is a view in side elevation of a modiiied form of the apparatus,the housing of the apparatus being broken away fragmentarily tov showcertain elements u therein contained.

Referring to Figs. l and 2 of the drawings the apparatus comprises atank 1 in which a large body 2 of water is contained, the water beingcharged into the tank by a supply pipe 3 connected to the tank `at ornear its top. Either hot water may be delivered by a line 3a, or coldwater by a line 3b, depending upon Whether the apparatus s at the timein use as a heating or as a cooling unit. A sight glass 4 is arranged toindicate the water level in the tank, and a valved drain line 40 isconnected tothe bottom of the tank, whereby the tank may be drained oncea year, say, for inspection.- A safety valve 50 is provided on the tank,to safeguard the apparatus in the event that excessive vapor pressureshould develop therein.

A plenum chamber 7, formed with `heat-conducting walls of sheet metal,is supported on legs 8 within the body of water, and a plurality ofcoiled tubes 9, communicating at their lower ends with the interior ofchamber 7, extend upwardly through the water and the cover 1a of thetank, where they open severally into ducts 11 that lead to the rooms tobe air conditioned.

A blower 12, driven by a belt 12a and an electric motor 12b, draws airthrough a renewable ilter 13, from a receiver chamber 14, into which, byWay of a header 15a, ducts i5 return air severally from the roomsservedv by nited `States Patent O Cil the delivery ducts 11. The blower12 delivers filtered air through a pipe 16, plenum chamber 7, pipe coils9, and ducts 11 to the rooms to be serviced. In dowing through the pipe16, plenum chamber 7 and pipe coils 9 the filtered air is thermallyconditioned by the enveloping body of water 2. Thus, a continuouscirculation of air is established through the air conditioning apparatusto the rooms served and back to the apparatus; that is to say, filteredand conditioned air delivered to the rooms, and spent air from the roomsis returned for reconditioning. The receiver chamber 14 includes anadjustable inlet 17, by means of which a desired quantity of new ormake-up air is admitted from the outer atmosphere to the circulatingstream.

Advantageously a single cabinet, formed of sheet or plate steel, isadapted to provide a unitary enclosure for the entire apparatus, savefor the ducts 11 and 15 leading to and from the rooms to be conditioned.A transverse partition 1b defines the length of the Watercontainingtank, and a partition 1c defines within the cabinet the air-lilteringreceiver within the cabinet, while the space between partitions 1b and1c, together with the space below partition 1c, provides room for theblower 12, its drive 12a, 12b and a refrigerator unit 6, presently to bedescribed. As shown in Fig. l, a door 1d on the side of the cabinetgives access to the space or so-called machinery compartment within thecabinet to the right of partition 1b, whereby the blower, blower driveand refrigerator unit may be serviced, and the lilter 13 removed forcleaning or replacement.

Heat-exchange means are provided for maintaining the body 2 of waterat atemperature selectively either above or below normal or roomtemperature, depending on whether the rooms are to be heated or cooled.Such heat-exchange means comprise two thermal systems havingheat-conducting walls, each system containing within its walls means fordeveloping temperatures at substantial variance with the temperature ofthe body 2 of water. One system comprises a heat-abstracting or coolingdevice in the form of a coiled evaporation or expansion tube 5 of therefrigerator unit 6. The refrigerator unit may be a conventional pieceof equipment which compresses and condenses a fluid refrigerant, expandsor evaporates the condensed refrigerant in tube or coil 5, and draws theevaporated refrigerant back to the unit. It is needless to concern thisspecification with the structural details of the refrigerator unit;suice it to say that the unit may be connected to a source of electricalpower by circuit wires 60, and that as long as the unit remains inoperation the evaporating and expanding refrigerant forms means withinthe walls of coil 5 for abstracting heat from the body 2 of water.

The unit 6 may be responsive to the usual thermostatic controls (notshown) whereby, when the temperature of the room or rooms to be airconditioned rises to a predetermined value, the unit is caused tooperate automatically to cool the body of water 2, and the cool water iscaused to cool air that is delivered into the rooms. When thetemperature of the rooms falls to desired value, the thermostaticcontrols automatically arrest the operation of the unit 6, and thus 'theon and olii operation of the unit 6 may be automatically controlledduring hot weather to maintain the desired temperature in theairconditioned rooms. The thermostatic controls are well known to theart and this specification need not be further involved with them.

The second heat-exchange system of the apparatus comprises a heatingdevice in the form of one or more tubes I8 whose walls are formed ofheat-conducting metal, and within such walls means are provided forgenerating heat for transfer to the body 2 of water. The 4heating meanswithin the tube 1S may be an electrical resistor of well-known type,energized by electrical current delivered through circuit wires 61.Alternatively, gas `or other fluid fuel may be burned within the tube todevelop the essential heat. Accordingly, the water may be heated, andsuch heat may be transmitted from the water, through the walls of theplenum chamber 7 and coiled ducts 9, to the air delivered to the roomsto be air-conditioned. It will be understood that conventionalthermostatic instruments may be arranged to control the operation of theheat-generating means within the tube or tubes 18, so that, during coldweather, when the temperature within the rooms falls below that at whichthe functioning of the refrigerator unit 6 is designed to hold it, heatis automatically developed in the tube 18 and the water 2 heated, withthe effect that the air delivered to the rooms is heated, until thetemperature in the rooms rises to substantially the point at which therefrigerator unit is designed to cool the room. Then the generation ofheat in tubes 18 is arrested.

Thus it is that in all kinds of weather the apparatus is eective tomaintain the serviced rooms at desired ternperature.

It will be perceived that when either of the heat-exchange systems 5, 6or 18 is in operation there is a transfer of heat to or from the body 2of water. This transfer of heat may be termed a primary heat transfer.In consequence of the operation of either heat-exchange system, underthe conditions described, the temperature of the body of water isnormally held at substantial variance with that of the air circulated bythe blower 1.2, whereby there is a heat transfer between the body ofwater and the air flowing through the duct 16, the plenum chamber 7 andthe coiled ducts 9. The latter transfer of heat may be known as asecondary heat transfer.

We now come to a feature of importance, a feature that forms a majorcontribution to the improved utility and high thermal efficiency of theapparatus of the invention.

It has already been mentioned that the plenum chamber 7 is mountedwithin and enveloped by the body 2 of water at a substantial intervalabove the bottom (1e) of the tank 1. The tube elements and 18 of the twoI heat-exchange systems of the apparatus are arranged at an intervalabove the bottom of the tank and at an interval below the lioor of theplenum chamber 7, and are entirely enveloped or surrounded by, andimmersed in, the water above the tank bottom and below the plenumchamber licor. This structural organization affords greater operationaladvantages and higher thermal eiiciency than is to be found inpre-existing structures in the air-conditioning art.

It is contemplated that a system of baiies may be provided in the plenumchamber to obtain a tortuous and elongated course of flow of the airthrough such chamber, but such structural detail, apart from theimproved assembly described above, is known to the art, whereforeillustration is not required herein.

In some cases the apparatus may be required to serve only as a roomheater, in which event the Water-cooling system (5, `6) will be omittedfrom the assembly of Figs. 1 and 2. And in those cases where theapparatus is installed immediately in 'the room to be heated, the ducts11 and 15 may be omitted. The air passing through the apparatus may bedrawn from the room through a single inlet, and the heated air delivereddirectly into the room. For example, as shown in Fig. 3, the blower 120may be mounted on one end wall of the tank 100, and the blower may bedirectly driven by the motor 121. The air is drawn through the inlet ofthe blower, delivered through the plenum chamber 70, through the singlecoiled duct 90 into a chest 91, and thence delivered through louveredopenings 92 in the wall of the tank into the room. It will be understoodthat in the simplied Vor modified apparatus of Fig. 3 the water-heatingy 4 duct 180 of the heat-exchange system is disposed above the bottomofthe tank and below the oor of the plenum chamber, in the particularlyeffective organization described of the ducts 5 and' 18 of the apparatusof Figs. l and 2.

In further modication, if the apparatus is desired to serve as a coolingunit, the structure shown in Fig. 3 will serve, modied only by thereplacement `of the duct 180 by the coiled duct 5 of Fig. 2, and bymounting the refrigerating unit 6, either within the cabinet, as in Fig.2, or any suitable place externally of the tank 100.

The helically coiled form of the submerged tubes 9 and is a matter ofimportance. Not merely does such form of the tubes' afford within a tankof specified dimensions maximum area of thermal transfer between thecontained liquid and the air passing through the apparatus, but equallyor more important the particular form of the tubes tends to dampen aviolent flow of the air from the plenum chamber into the discharge ducts11 (Figs. 1 and 2) or the discharge chest 91 (Fig. 3), whereby aso-called draftless How of air into the serviced rooms is obtained.

Various other modifications will occur to those skilled in the art,without departing from the spirit of the invention defined in theappended claims.

I claim:

1. Air conditioningapparatus comprising a cabinet, a transverse verticalpartition in said cabinet forming a machinery compartment and an airconditioning compartment, a body of'water in said air conditioningcompartment, an air receiver chamber in said machinery compartmentadapted to receive air to be conditioned, a blower in said machinerycompartment having its inlet connected to said receiver chamber, anoutlet pipe leading from said blower through said partition into saidair conditioning compartment, a plenum chamber mounted in said airconditioning compartment and enveloped by said water, said outlet pipebeing connected thereto, a helically coiled outlet tube leading fromsaid plenum chamber and extending through a wall of said airconditioning compartment, the capacity of which is substantially lessthan that of said plenum chamber, a heating tube within said airconditioning compartment and enveloped by said water and being mountedabove the floor of said tank and below said plenum chamber, arefrigerant tube within said air conditioning compartment enveloped bysaid water and being mounted above said tank iioor and below said plenumchamber.

2. Air conditioning apparatus as deined in claim l, with a plurality ofhelically coiled tubes having total capacity smaller than that of saidplenum chamber and extending through a wall of said air conditioningcompartment.

3. Air conditioning apparatus as defined in claim 1, saidmachinerycompartment containing a refrigerating unit connected to saidrefrigerant tube.

4. Air conditioning apparatus as defined in claim l, said receiverchamber having a filter mounted therein to filter the airreceived priorto its entry into said blower.

5. Air conditioning apparatus as defined in claim l, said heating tubehaving electrical heating means mounted therein.

References Cited in the file of this patent UNITED STATES PATENTS580,795 McCarthy Apr. 13, 1897 1,704,535 Gralin Mar. 5, 1929 1,747,070Graftlin Feb. 11, 1930 1,747,134 Posey Feb. 11, 1930 1,875,752 MonteroSept. 6, 1932 2,216,175 Helbing Oct. 1, 1940 FOREIGN PATENTS Y 101,897Australia Sept. 9, 1937

